What is the importance of seeds in plants?

Seed is a ripened plant ovule or propagative part of plant formed in the sexual reproductive cycle of Gymnosperm and Angiosperm plants. It consists of protective coat enclosing embryo and food reserve. They are important because:

​1.Seeds have reserve food for nourishing the young seedlings till they become nutritionally independent.
2. Seeds are formed through sexual reproduction, hence they carry a number of variations. 
3. Seed can be stored for later use. This is helpful for supply of food throughout the year.
4. Seed is dry with dormant embryo and thick protective seed coat. It is most suitable for perennation through unfavourable conditions.